The present invention relates to an eye characteristic measuring apparatus where light quantity distribution characteristics of a measuring target image projected to a fundus of an eye to be inspected are detected, and eye optical characteristics are measured from the light quantity distribution characteristics.
In the prior art, an apparatus is known where an illumination image is projected to a fundus of an eye to be inspected, and an image formed by reflected bundle of rays from the fundus of the eye is condensed onto a photoelectric detector, and based on a signal from the photoelectric detector, the light quantity distribution of the reflected image in the fundus (for example, point image light quantity distribution characteristics) is detected, and eye optical characteristics of the eye are measured from the light quantity distribution characteristics detected.
This kind of apparatus is said to desirably use a laser light source or SLD (Super Luminescent Diode) as a light source for bundle of rays projected to a fundus in order to increase the reflected light quantity.
When bundle of rays from such a light source is utilized, however, a speckle noise is inevitably produced to an image formed on the photoelectric detector, and unevenness of the light quantity is produced and the speckle noise becomes obstruction while the light quantity distribution characteristics of the image are measured, resulting in that the measurement cannot be performed with high accuracy.
The present invention intends to solve such problems in the prior art, where a deflection member is rotated and thereby a speckle noise is averaged for an image formed on a light receiving element, and the image can be detected as an image free from the uneven light quantity and the light quantity distribution characteristics can be measured with high accuracy.
The present invention is in an eye characteristic measuring apparatus for detecting light quantity distribution characteristics of a measurement target image projected to a fundus of an eye to be inspected, and for measuring eye optical characteristics from the light quantity distribution characteristics, where a projecting optical system has a light source and by bundle of rays emitted from the light source, a measurement target is projected to the fundus of the eye, and a light receiving optical system condenses the bundle of rays reflected from the fundus of the eye. A photoelectric detector detects light quantity distribution characteristics of an image formed by the light receiving optical system, and an arithmetic unit measures eye optical characteristics of the fundus of the eye based on a signal output from the photoelectric detector. A deflection optical member is arranged rotatably for deflecting bundle of rays incident into both optical paths of the projecting optical system and the light receiving optical system.